摘要 |
Features of a mask, when close enough to one another, can cause unwanted phantom images to print on an integrated circuit. Advantageously, potential locations of phantom images can be automatically identified from a mask layout. This technique can include creating perimeters or rings around features in the mask layout (in one case, after proximity correction). An overlap of perimeters/rings can be assigned a particular weight such that areas of greater overlap have a higher weight and areas of less overlap have a lower weight. If the weight of an overlap area exceeds a trigger weight, then an evaluation point can be added to the mask layout, thereby identifying that layout location as a potential location of a phantom image. After simulation of the mask layout, that layout location can be analyzed to determine if a phantom image would print.
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